JPH11197905A - Method for loading workpiece onto lathe and loader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of loading a workpiece onto a lathe, in which there is used a technical measure such that the workpiece can be fed without stopping a spindle even though the workpiece has a large rotary inertia or requires phase adjustment. SOLUTION: A hand drive motor to be NC-controlled is provided on a loader 10. Hands 14 (14a, 14b) of the loader 10 are rotated at a speed synchronized with that of a spindle of a lathe, having a phase synchronized with that of the latter, as necessary, by means of the hand drive motor before a workpiece is delivered relative to the lathe. With the timing during the lathe processing a preceding workpiece, an instruction for rotation, which is based upon data of rotation of a spindle during the delivery of the workpiece, is delivered to the hand drive motor so as to initiate the rotation of the hands. Then, the rotational speed of the hands are increased up to a speed corresponding to the data of rotation of the spindle until the hands are opposed to the spindle 1 of the lathe after the completion of the process of the preceding workpiece, and after the confirmation of a synchronized condition between the spindle and the hands, the workpiece is delivered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of loading a work on a lathe and a loader (including one having an unloading function) used for carrying out the method. The present invention relates to a technical means capable of performing loading and unloading.

[0002]

2. Description of the Related Art A loader for supplying a workpiece to a lathe includes a gantry type and a swing arm type, and any type of loader is provided at a tip of an arm inserted into and removed from a machining area of the lathe. The hand is gripped by the hand and the work is transferred between the work table and the work conveyor and the lathe. A general work cycle of a workpiece on a lathe provided with such a loader is as follows.

While the preceding work is being processed by the lathe, the work loader grasps the next work and waits. When the previous work is completed, a retreat command is given to the tool rest and a stop command is given to the spindle. When the retreat of the tool post is completed, open the cover of the lathe and insert the hand into the machining area of the lathe, wait for the spindle to stop, and transfer the work between the hand of the loader and the chuck of the lathe, After the arm starts the evacuation operation, start the rotation of the main shaft.When the hand retreats outside the machine, close the cover of the lathe, advance the tool post, and confirm that the main shaft rotation has reached the predetermined number of rotations. Then, the processing of the newly loaded work is started.
The loader moves the hand to the work table or the work transfer conveyor while the lathe is processing the work, transfers the work to and from them, grasps the new work, moves to the lathe, Wait for the machining of the work to be completed.

[0004] By repeating the above cycle, the supply, processing and discharge of the workpieces to a plurality of workpieces are automatically performed. In the case of discharging the work using the dropping operation of the work, open the chuck of the lathe before transferring the work to and from the loader, and move the chuck to the bucket or chute waiting below. Drop the processed work.

The transfer of the work between the loader and the lathe in the above-described machining cycle is performed while the main spindle of the lathe is stopped. On the other hand, as a technical means for transferring a work to and from a loader while rotating a main shaft of a lathe, an apparatus for transferring a work to and from a hand rotatably provided is provided. When such a loader is used, when the hand of the loader and the chuck of the lathe hold the work at the same time during the transfer of the work, the hand rotates following the rotation of the main shaft, so the rotation of the main shaft is stopped. Work can be delivered without doing so.

[0006]

When a workpiece is transferred between a lathe and a loader while the spindle is stopped, the spindle must be stopped and restarted before and after the transfer of the workpiece. Must. In a small lathe, the rotational inertia of the chuck and the work is smaller than the torque required for the spindle for cutting, so that the spindle can be stopped and restarted in a short time. However, if the lathe is of a medium or large size, the rotational inertia of the chuck and the work becomes large, so that it takes time to stop and restart the rotation of the spindle. The work transfer operation and work processing operation are started after confirming the stop of spindle rotation and the rise of the spindle rotation to the specified number of revolutions, so it takes time to stop and restart the spindle rotation. In such a case, the loader and the tool rest are on standby during that time, and a waiting time is generated during the processing cycle of the work, which is an obstacle to improving the processing efficiency.

[0007] On the other hand, in a device in which the hand is freely rotatable and the hand is rotated by following the main shaft at the time of transfer of the work, the hand is instantaneously rotated when the work is simultaneously held by the chuck of the main shaft and the hand of the loader. Since it is necessary to start, that is, it is necessary that the rotational inertia of the hand or the work is small, it is difficult to adopt it for a medium-sized or large-sized lathe, and there is a problem that the surface of the work is damaged when the work is delivered. Also, with such means, the phase of the workpiece and the spindle cannot be synchronized at the time of workpiece transfer.Therefore, the workpiece has a hexagonal or square gripping portion, or a protrusion or notch is formed on the peripheral surface, so that A work or the like that must be machined in a fixed direction cannot be supplied.

According to the present invention, a work having a large rotational inertia,
It is an object of the present invention to provide a loading method and a loader that can supply a workpiece to a lathe without stopping the spindle, even for a workpiece that needs to be supplied in phase.

[0009]

According to the present invention, a loader is provided with N
C is provided with a hand drive motor 20 which is controlled before hand transfer to and from a lathe.
By rotating the loader hand 14 at a synchronous speed with the spindle of the lathe at 0 and with a synchronous phase if necessary,
The above problem has been solved.

That is, in the method of loading a work onto a lathe according to the present invention, a hand drive motor for driving a hand provided at the tip of an arm inserted into and removed from the machining area of the lathe is provided, and the hand drive motor is provided between the lathe and the spindle. Prior to the work transfer operation, the hand is rotated by the hand drive motor in synchronization with the rotation of the spindle of the lathe, and after confirming that the spindle of the lathe and the hand of the loader are rotating synchronously, the hand between the lathe and the loader is The operation of transferring the work between the two is started.

According to a second aspect of the present invention, in the above-mentioned method, the rotation command is given to the hand drive motor based on the rotation data of the main shaft at the time of workpiece transfer at a timing while the lathe is processing the preceding workpiece. After the rotation of the hand is started, after the processing of the preceding work is completed, the hand of the loader is rotated to the rotation corresponding to the rotation data of the spindle until the arm of the loader is inserted into the machining area of the lathe and the hand is opposed to the spindle of the lathe. It is characterized by starting rotation of.

Further, the work loader according to the present invention comprises an arm 13 inserted into and removed from a machining area of a lathe, and a hand 1 rotatably mounted around a rotation center axis of a work gripped at the tip of the arm.
4, a hand drive motor 20 for driving the hand to rotate about the rotation center axis, and a controller 26 for controlling the rotation of the hand drive motor 20 based on the rotation data of the main shaft set in the NC device 27 of the lathe. It is provided with.

According to the method of the present invention, the rotation of the hand of the loader is synchronized in advance with the rotation of the main shaft at the time of transferring the work, and the work is transferred after confirming the synchronization between the two. When the rotation speed and phase are specified between the hand and the workpiece held by either of them, there is no phase shift, that is, the work is performed under the same conditions as when the spindle is stopped and the delivery is performed. The workpiece can be smoothly transferred to and from the loader while the main shaft is rotated even if the workpiece has a large rotational inertia.

Further, since the rotation command to the hand of the loader is given based on the rotation data of the spindle at the time of transferring the work, the transfer operation of the work can be started immediately after the machining of the preceding work is completed.

Further, by giving a rotation command to the hand drive motor with sufficient time margin during the processing of the preceding work, even if the hand is slowly accelerated, the hand can be rotated to a desired rotation by the time of work transfer. The rotation of the hand and the medium and large-sized work held by the hand can be synchronized with the rotation of the main spindle by the small-capacity hand drive motor. Since a small-capacity motor is inexpensive and occupies a small space in the motor body and the servo device that controls the motor body, the device can be provided at low cost.

[0016]

FIG. 2 is a front view schematically showing a lathe provided with a gantry type loader. In the drawing, 1 is a spindle, 2 is a headstock, 3 is a chuck mounted on the tip of the spindle, 4 is a tool rest, 5 is a tool turret, and 6 is a tool mounted on the tool turret. The lathe bed and the tool post feed mechanism are not shown. Reference numeral 10 denotes a gantry type loader, and reference numeral 30 denotes a work table. The loader and the frame of the work table are not shown. A is a machining area of the lathe.

The work table 30 is arranged on the lathe opposite to the headstock 2 on the side opposite to the machining area. The loader 10 has a horizontal rail 11 mounted above the headstock 2. A carrier 12 that runs along the rail 11 is mounted on the rail 11, and the carrier 12 includes an arm 13 that moves up and down.
At the lower end of the arm 13, a hand 14 (14
a, 14b) are provided. The rail 11 extends from above the work table 30 to above the processing area A. The movement of the carrier 12 and the raising and lowering of the arm 13 cause the hand 14 to move to the position facing the work table 30 across the work and to the chuck 3 of the lathe. It is possible to move to an opposing position.

As shown in FIG. 3, the lower end of the arm 13 has a pivot shaft 1 supported at an angle of 45 degrees downward toward the chuck 3.
A hand frame 16 is provided which is rotatable around 5 and a pair of two hands 14a, 14b in which one is horizontal and the other is vertically downward.
Is provided. Each hand 14a, 14b is provided on the hand frame 16 so as to be freely rotatable around a rotation center axis of a work gripped by the hand, and bevel gears 17a, 17b provided substantially integrally with each hand are:
It meshes with a bevel gear 19 provided at the tip of a drive shaft 18 that penetrates a hollow hole of the turning shaft 15 of the hand frame. The base end of the drive shaft 18 is connected to the output shaft of a hand drive motor 20 mounted on the hand frame 16. The hand frame 16 is connected to the hand frame 16 via a bevel gear 21 fixed integrally therewith.
The motor is intermittently driven around the turning shaft 15 at an angle of 180 degrees by a turning motor provided on the back side of the paper of FIG.

The hand drive motor 20 is connected to the servo controller 2
5 is controlled by an NC controller 26. The NC controller 26 includes, in the lathe-side NC controller 27, data on the number of revolutions of the spindle when the workpiece is transferred and the phase of the spindle detected by the spindle encoder. And data is given.

The hands 14a and 14b shown in FIG. 3 can switch between a hand horizontally opposed to the chuck and a hand vertically opposed to the work table by rotating the hand frame 16 by 180 degrees. For example, the workpiece on the work table 30 is gripped by the downward hand and moved to the processing area A, and the horizontal hand is opposed to the chuck 3 of the lathe to receive the processed workpiece. An operation of transferring a new work to the chuck with the new work facing the chuck, moving the work to the work table 30 in the same posture, and transferring the processed work gripped by the downward hand to the work table 30 can be performed. .

In the hand having the structure shown in FIG. 3, the hand for receiving the processed work from the chuck of the lathe and the hand for transferring the new work are synchronously driven by one hand drive motor 20, so that the main spindle of the lathe is used. While rotating at a constant speed, it is possible to take out a processed work and load a new work. If the processed work is to be discharged by dropping, it is sufficient to provide only a hand for supplying the work to the loader.

For a workpiece that needs to be loaded with its phase adjusted to the phase of the main spindle, a projection or the like for regulating the phase of the workpiece is provided on the workpiece mounting table 30, and the workpiece mounting table 3 is provided.
The direction of the workpiece on 0 is registered in advance in the NC controller 26 of the loader. The hand drive motor 20 is provided with an encoder so that the rotation speed and phase of the hand can be detected.

FIG. 1 is a flow chart showing one example of the work transfer method of the present invention. The procedure shown in this flowchart is such that the rotation of the hand 14 is started while the lathe is processing the preceding work, and thus the hand of the loader is waiting outside the cover covering the processing area A of the lathe. Be started. First, a hand rotation command is given to the hand drive motor 20 in the first step S1. The commanded rotation speed is the rotation speed at the time of workpiece transfer, and is usually the rotation speed at the end of machining of the preceding work or the rotation speed at the start of machining of a newly loaded work. Next, in a standby step of S2, the process waits until the loader arm 13 can be inserted into the machining area A of the lathe.

The rotation of the hand 14 is gradually accelerated during this waiting period, and approaches the commanded speed. When the loader arm can be inserted into the machining area of the lathe, the loader arm 1
3 is lowered (step S3), and the hand facing in the horizontal direction is opposed to the chuck of the lathe. Next, check step S
In step 4, the output of the spindle encoder is checked to confirm whether the spindle rotation is the set rotation at the time of workpiece transfer. If the spindle is not rotating at the time of workpiece transfer, an alarm indicating that the spindle rotation speed is not the command rotation speed is displayed in step S41, and the loading operation is stopped in step S42.

If the spindle rotation is the set rotation, it is checked in a confirmation step S5 whether the rotation of the hand 14 has reached the set rotation. If the rotation of the hand 14 has not reached the set rotation, the process waits. If the rotation of the hand 14 does not reach the set rotation even after the set standby time has elapsed, steps S51 to S52 are performed.
Then, an alarm indicating that the hand rotation does not reach the command value within a predetermined time is displayed, and the loading operation is stopped in step S53.

If the hand is a command rotation, step S6
Move the hand horizontally toward the chuck with
The work is delivered. In the case of the hand shown in FIG. 3, the operations in steps S6 and S7 are performed twice with the horizontal retreat operation of the hand and the 180-degree turning operation of the hand frame being interposed on the way, and the processed work and the new work are performed. Is passed.

Next, after the hand retreats in the horizontal direction in step S8, the arm 13 is raised in step S9, so that the hand retreats from the machining area A of the lathe to carry out the work transfer operation with the lathe. finish.

In the above procedure, the rotation of the main shaft and the hand are compared with the set rotation to confirm the rotation synchronization between the main shaft and the hand. It is of course possible to do In the case of a work that requires phase synchronization at the time of loading, it is also checked whether the phases are synchronized at the same time as checking the rotation speed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an example of the method of the present invention.

FIG. 2 is a front view schematically showing an example of a lathe provided with a loader.

FIG. 3 is a schematic cross-sectional view showing an example of a hand rotation drive mechanism.

[Explanation of symbols]

 1 Spindle 10 Loader 13 Arm 14 (a, b) Hand 20 Hand drive motor 26 NC controller 27 NC controller

Claims (3)

[Claims] A hand drive motor for rotating a hand provided at the tip of an arm inserted into and removed from a machining area of a lathe;
Prior to the transfer of the workpiece to the lathe spindle, the hand drive motor rotates the hand in synchronization with the lathe spindle rotation, and confirms that the lathe spindle and the loader hand are rotating synchronously. A method of loading a work onto a lathe, characterized by starting a work transfer operation between the lathe and the loader after the work is completed. 2. A turning command is given to a hand drive motor based on rotation data of a spindle at the time of workpiece transfer at a timing when the lathe is processing a preceding workpiece, and rotation of the hand is started, and the turning of the preceding workpiece is started. After the processing is completed, the rotation of the hand is started up to a rotation corresponding to the rotation data of the main spindle until the hand of the loader is inserted into the processing area of the lathe by inserting the arm of the loader and the hand faces the main spindle of the lathe. A method for loading a work on a lathe according to claim 1. 3. An arm 13 inserted into and removed from a machining area of a lathe;
A hand 14 rotatably mounted around the rotation center axis of the work gripped at the tip of the arm, a hand drive motor 20 for rotating the hand about the rotation center axis,
A lathe work loader, comprising: a controller 26 for controlling the rotation of the hand drive motor 20 based on spindle rotation data set in the lathe NC device 27.